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By MOHAMMED AMINE BELMI, ANAS DRIOUCH, ABDELAZIZ LAHMILI, LATIFA OUADIF

The mineral industry uses significant amounts of water in processing. Thus, sustainable practices with the processing of ores are of critical importance. An impact tester was used to measure the adhesion force between particles and a glass disk [1,2]. A removal force was caused by the impact of the disk/particle containing a puck with a stopper. Johnson-Kendall-Roberts (JKR) theory [3] was used to determine the interfacial energy between the particles and the substrate. Capillary condensation of water can occur between the particle and surfaces in humid environments. The adhesion of particles on rough surfaces has been studied previously [4-10]. The research presented herein combines both variables to separate particle types with minimal water usage.

By A. D. Davis

Naturally occurring arsenic has been detected in water from inactive mines and several wells in the Keystone area of the Black Hills. Keystone City Well #4 showed a total arsenic concentration of 69 parts per billion (ppb) during pumping in 2004. The well is not used currently except for arsenic-removal research. Water also can be pumped from a mine shaft in the abandoned Keystone ? Columbia ? Bullion gold mines, whose interconnected workings flooded after mining ceased in the 1930s. This water has been considered for local supplies, although it would require treatment or blending because of arsenic concentrations. According to historical records, the Bullion Mine produced 100,000 pounds of white arsenic. An aquifer test on the mine workings was performed at a pumping rate of about 550 gallons per minute. The arsenic concentration in pumped water was 33 ppb. In addition to wells within Keystone, samples from the water supply at nearby Mount Rushmore National Memorial have shown arsenic concentrations greater than 10 ppb, the U.S. Environmental Protection Agency?s maximum contaminant level for arsenic in drinking water. Limestone-based technology for removal of arsenic from drinking water is an innovative and promising method that has been considered for treatment of water at Keystone. In batch testing with water from Keystone Well #4, limestone removed about 65% of arsenic from solution. A related problem of arsenic removal from drinking water involves disposal of the waste product, which is critical for commercial viability of removal technologies. Current research is investigating thermal stability of the waste in order to determine the potential for recycling of the material during manufacture of cement.

Jan 1, 2010

By V. Roze, R. N. Parkinson, R. Shepherd

The alphaDOSIMETER is a complete, integrated system designed to monitor the immediate worksite of underground miners where the disintegration for radon daughters is a risk to the health of mining personnel. The dosimeter weighing little more than one pound is worn by each miner throughout the entire shift and is powered by the miner's cap lamp battery. After this integration period, the unit is connected to a reading network whereupon the day's data is dumped, calculated and stored. Beginning in July 1980, prototype units were subjected to vigorous underground testing in uranium mines in Canada and the United States and in tin mines in Cornwall, U.K. The testing results are summarized and proposals advanced for a typical mine monitoring system utilizing the alphaDOSIMETER.

Jan 1, 1981

By D. Berberick, G. Sturgis, M. Board, B. Strickland

"Hecla Limited is nearing completion of the Lucky Friday Mine No.4 shaft located in Mullan, ID. The shaft is collared at the 4940 level of the mine and will have a final mine level depth of 8620, or 9,590 feet below the surface. After reaching the 7400 mine level the shaft encountered ground deformation higher then allowed for in the design for a circular shaft excavation and concrete lining. This additional ground deformation required portions of the shaft concrete liner to be reinforced with frameless, steel liner plate. To eliminate the installation of the liner plate from the remaining shaft development, the design of the shaft excavation starting at the 7650 mine level was changed to an elliptical cross section based on the overall stress field orientation as well as the orientation of the structure of the host rock surrounding the shaft. The elliptical cross section was instrumented to confirm the shaft excavation and lining was performing as designed. This design change has allowed the shaft to continue to the planned 8620 mine level without the need to install liner plate in the shaft or change the overall functionality of the shaft or the Lucky Friday life of mine plan.INTRODUCTION Hecla’s Lucky Friday Mine is a deep, underground producer of silver, lead and zinc in the Coeur d’Alene mining district of northern Idaho (Figure 1). Primary access into the mine is via the Silver Shaft, a 5.5-m (18-ft) diameter, concrete lined shaft sunk to an original depth of 1,890-m (6,200-ft). Current production is from the Gold Hunter vein system, approximately 1,525-m (5,000-ft) northwest of the Silver Shaft.Lucky Friday’s #4-Shaft is a 5.5-m (18-ft) finished diameter, internal shaft, or winze, being sunk to the north of the Gold Hunter vein system, from the mine’s 4760 level, 1,743-m (5,720-ft) below the surface, to the 8620 level, 2,923-m (9,590-ft) below the surface. The shaft is designed to provide access to the deep, high-grade zones of the Gold Hunter in order to increase the mine’s production and operational life. Design and engineering began in 2006, with construction starting in the fourth quarter of 2009."

Jan 1, 2016

By James R. Taylor

24.1-BASIC PRINCIPLES JAMES R. TAYLOR The basic principle involved in maintenance is protection of a company's investment through the care and upkeep of machinery and equipment, buildings and properties. Maintenance is justified through making available to the maximum extent possible the facilities, machines and services required by the operating and production departments in their function of insuring optimum return on investment. As the size, cost and complexity of the equipment used in modern mining and related industries increase, operating and production personnel become proportionately more dependent upon maintenance engineering for its contribution to the overall profit picture. A greater part of the total cost now is charged to maintenance and the maintenance group becomes a major company unit. Basic maintenance concepts have changed very little over the years, but the advances in methods and technique have brought about tremendous challenge and have in consequence assumed a greater influence and importance. The older "sledge- hammer" methods have given way to engineered and scientific systems, while the accelerating development of intricate equipment and machinery, and the instrumentation essential for control, demand an ever-increasing upgrading of maintenance personnel. Regardless of this growth in importance, cost and complexity of the maintenance function, it is important to remember that it is not an independent and self-sufficient unit, but is a necessary facet of the entire plant operation and is subject to the company's total production effort. As one part of a team, maintenance is successful only when functioning cooperatively wit11 the other departments it serves Close collaboration in all areas served by n maintenance group is essential if it is to function fully to protect the company's investment, whether the assets are in machinery, materials or people. 24.1.1-MAINTENANCE SCOPE Maintenance functions may be grouped into the two general classifications of primary and secondary. This grouping constitutes a basic division although, in practice, the scope of the maintenance activity varies in each mine or plant and is subject to differences in size and type of operations and company policy, plus the influence of precedent, which may be sectional or industry-wide. The primary functions supply the justification for the maintenance engineering department. while secondary functions are variable according to plant conditions and needs. The primary functions may be categorized as follows: 1. Maintenance of existing machinery and equipment. 2. Maintenance of existing buildings and grounds. 3. Inspection and lubrication of equipment and machinery. 4. Utilities generation and distribution. 5. Alterations to existing equipment and facilities. 6. Installation of new equipment and facilities. 7. Instrumentation.

Jan 1, 1973

This review provides a new and comprehensive summary on studying colloidal interactions encountered in mineral processing with representative examples for critical information, which are of great scientific and practical importance. Colloidal interactions play a vital role in mineral processing, including grinding, physical separation (particularly flotation), dewatering and tailings management (Fig. 1). Despite great energy input in comminution to liberate valuables from gangues, hetero-coagulation between valuables and gangues would prevent the separation of valuables from gangues. On the other hand, selective coagulation/flocculation to increase the size of desired fine particles could enhance physical separation and dewatering, while dispersion is needed for fine grinding. The importance of colloidal interactions is becoming increasingly significant as we process ever more finely disseminated low-grade ores as a result of inevitable depletion of high-grade ore deposits. To control the state of colloidal dispersions by creating favorable conditions, it is of paramount importance to study colloidal interactions in a relevant system and understand underlying mechanisms. 

By J. Groff

The Getchell and Twin Creeks mines are located along a north-northeast trending structural zone in Humboldt county, Nevada approximately 40 miles northeast of the town of Winnemucca. Gold mineralization at the Getchell mine is represented principally by sulfide-rich ores, which contain significant amounts of realgar and\ orpiment, with the gold being recovered through processes which involve pressure oxidation. In contrast, oxide ores are currently being mined and processed at the Twin Creeks mine although large reserves of sulfide ores, some of which contain orpiment-realgar-stibnite, have been defined (Bloomstein et al., 1990). The Getchell and Twin Creeks mines represent major gold orebodies but very little has been published pertaining to mineral paragenesis and the characteristics of ore-forming fluids for these deposits.

Jan 1, 1994

By Mark R. Stanton, Douglas B. Yager

Integration and synthesis of mine-site topography, geophysical, and geochemical data yields both two- dimensional and three-Amensional perspective models for the May Day mine located in the Cement Creek drainage near Silverton, Colorado. Induced polarization, geophysical data are spatially registered with geochemical data acquired from drill hole cuttings that are contoured m three-dimensional space, thereby permitting determination of the most metalliferous and sulfur rich zones of a waste pile. This spatial modeling application was developed to be a visually intuitive tool to aid in mine waste reclamation.

Jan 1, 2000

By Barbery G., A. Maachar, M. Bourassa

Laboratory testing for flotation circuit design is carried out on a routine basis in a large number of lab- oratories throughout the world. Usually a sample of ore, assumed to be characteristic of the material to be processed in a future plant, having a mass of the order of a few kilograms, is ground in a batch ball or rod mill, in the presence of water and some re- agents (for pH control, etc. .. ); after dilution to the adequate solid concentration, the resulting slurry is transferred into a laboratory batch flotation machine, having a volume which can vary from 0.5 to 8 10 -3m3. Various types of machines are in common use, manufactured by the same companies that market industrial size flotation machines. The operation of flotation in the laboratory is carried out by an experienced technician, who uses parameters such as impeller rotation speed, air flowrate addition, froth height, froth removal rate, in conjonction with reagent addition sequence, to "test" the ore. After flotation, the froth products ("concentrates"), and the solids remaining in the cell are filtered, dried, and analyzed for the various elements of interest. For flotation circuit design, a kinetic test is usually carried out, in which the froth products obtained at various times are collected to assess the time response of the ore in the laboratory machine with the combination of reagents used. Although this description is rather sketchy, it enables to outline some of the major difficulties in using laboratory data for flotation circuit design: 1. ore sample representatively 2. feed preparation procedure (laboratory compared to industrial scale) 3. laboratory procedures (type of ma- chine, type of operation, experimental errors. . . ) 4. flotation machine scale-up 5. flotation kinetic scale-up 6. flotation circuit design using laboratory data These various points will be discussed in the present paper, in order to stress the problem areas as well as possible solutions. ORE SAMPLE REPRESENTATIVITY It has been stated many times that one of the major problem in designing a flotation circuit is the representatively of the sample to be taken. Sampling of an ore body during prospection and evaluation is a specialized field, which has been progress in with the introduction of geostatistics. The application

Jan 1, 1986

By Katherine Hynard, Colin Eustace

Development quarterly mine plans is generally time-consuming and requires consideration for many operational constraints and competing objectives. With lengthy turnaround times, there is often limited opportunity to adjust the quarterly plan details to account for differences between actual state of the mine operation at the time of execution and expected state at the time that the plan was developed. Actual mining task completion times can vary significantly from the expected task completion times, due to many factors. In the absence of revision to account for differences between the planned and actual state, resource allocations and mining sequences, embodied in the quarterly mine plan may no longer be the best approach at the time of execution to achieve an efficient mining operation. Simulation and optimisation tools can be used to support rapid refinements for development and execution of weekly mine plans. When initialized with an operations data feed to establish the actual state of the mine operation, optimisation models can be used to facilitate both automation and revision of the quarterly plan to produce a weekly or daily plan for execution. This approach can remove much of the manual burden of revision if the existing quarterly plan no longer represents the best approach to meeting production objectives. Following initialisation with mining actuals, simulation models can provide a representation of the range of likely mine operations outcomes. The models can be used to accelerate the planning process by providing visibility of future performance and identifying likely operational issues. They can also be used to test the robustness of the plan with respect to performance variability and response to disturbances. Following identification of issues, simulation models can also be used for evaluating mitigation measures, through automated testing of alternative plans. Integration of mine data feeds with simulation and optimisation tools enables automated optimal responses to variations between the quarterly mine plan and actuals to be tested prior to release of and execution plan and implementation. The use of simulation and optimisation in weekly mine planning will be discussed in this paper with reference to surface mining examples.

Jun 25, 2023

By Robert J. Timko, R. Lincoln Derick

The Bureau of Mines evaluated the integrity of escapeways in a three entry underground coal mine. A center conveyor belt entry (secondary escapeway), was flanked by an intake (primary escapeway) and a return entry. Diesel equipment was used throughout the mine for material and personnel haulage. A carbon monoxide monitoring system, tied to a data recording computer on the surface, was deployed throughout the belt entry and at selected sites in the intake and return entries. Previously, the company had a fire of unknown origin in another mine, which prompted an interest in the performance of their escapeways. An initial, qua1itative evaluation was performed by burning approximately 14 kg of coal at the mouth of the intake entry. The first test was followed by a similar burn at the mouth of the belt entry. These initial trials showed a high quantity of leakage between entries. In several follow-up evaluations, simulated fires, using a tracer gas, were set in the intake and belt entries. Tracer gas concentrations were obtained in all entries at four different underground locations. The results of these tests showed that permanent stoppings could not guarantee isolated, contaminant-free escapeways.

Jan 1, 1989

By Richard M. Levine

Now that the former Soviet Union has divided into 15 countries, it is necessary to analyze separately the industrial mineral position of each of these countries. Industrial mineral data The former USSR was one of the world's largest producers of industrial minerals and had some of the world's largest reserves. Production and reserve figures, however, must be qualified. Even when these figures were reported by the Soviets, it was not clear that the production figures were for products that would be equally marketable in a competitive market economy. The reserve figures are based on the Soviet system of reserve classification, which is not directly equatable with the US Geological Survey and US Bureau of Mines classifications of economic reserves in market economy countries. The Soviets reserve classification system, in terms of which reserve figures will be given, is based on the reliability of the quantity of the material in place. The Soviet system assigns each occurrence to one of seven categories A, B, C1 and C2 are considered reserves; P1, P2, and P3 are considered resources. Mining in the former Soviet Union was authorized on the basis of the reserves in place in categories A, B and C, which had to be in prescribed ratios. However, the categories A, B and C do not necessarily correspond to Western concepts of material economically exploitable under present market prices with existing technologies.

Jan 1, 1992

By Jan M. Mutmansky

30.1-THE SCOPE OF SYSTEMS ENGINEERING JAN M. MUTMANSKY JAN M. MUTMANSKY 30.1.1-DEFINITIONS The terms "systems engineering," "systems analysis," and "operations research," common in today's technical literature, often are interchanged because of their similar meanings. However, some differences exist which need explanation. The most convenient way to achieve an understanding of the differences is to start with the definition of a system, namely, a collection of components which interact in a specific manner to accomplish a common objective. Accordingly, a haulage truck, a computer, a missile, a mining company or a nation each may be considered a system. Systems engineering generally can be defined as the conception, planning, design and engineering of any system of interacting elements so that the objective of the system is automatically optimized. Thus, systems engineering normally is con¬cerned with systems not yet activated.',' Systems analysis may be described as a scientific method of making decisions based on a quantitative or other objective evaluation of all action alternatives. It is very similar to systems engineering but usually is not considered to be restricted to problems of design prior to use. While the previous two disciplines are somewhat vague and can encompass a great variety of engineering functions, operations research can be more specifically defined as the application of mathematical models to the problem of optimizing the objective of any predefined system. Systems analysis and systems engineering are closely aligned sciences but opera¬tions research differs in the following ways. First, it generally is associated specifically¬with optimization and mathematical models while the other two often are not. In addition, it, is used predominantly on well-defined problems which can be ex¬pressed in mathematical terms. However, systems engineering or systems analysis may deal with highly complex social or governmental systems which may be ill¬defined and unsolvable by the classical methods of operations research. Finally, systems analysis and engineering always strive to look at the entire system to avoid the problem of suboptimization often necessary in operations research because of the necessity for a mathematical model. Because of his more extensive system, however, the systems engineer often is less able to find the optimal system. In summary, operations research, systems analysis and systems engineering are very similar in purpose but one, operations research, is more mathematical in nature and forms an important part of the other two activities. Other definitions which may be helpful are provided by Griffiths 3 Wilson,4 Falkic 5 Hall,2 Quade and Boucher, 6 and Flagle et al. 1 30.1.2-METHOD AND TECHNIQUES The systems or operations research approach makes use of scientific problem solving. The basic procedure comprises the following general steps: 1. Definition of the problem. 2. Construction of a model of the system. 3. Testing of the model under known conditions.

Jan 1, 1973

By Noel Jarrett

Energy consumption and distribution in aluminum production, conservation accomplishments, and future goals are presented. Electrolysis and electrode manufacture show the greatest promise for major improvements. Means are proposed for reducing waste heat generation in smelting and for conserving energy in anode manufacture by furnace design and substitution of other materials for petroleum coke. Hall-Heroult Process modifications, alternative designs, and the Alcoa Smelting Process are discussed as energy savers. Scrap recycling, more use of aluminum in transportation, and the installation of offshore smelters in less developed countries are shown to be additional means of coping with possible energy dislocations.

Jan 1, 1981

By David C. Slack

In recent years public concern over the environment has grown enormously. A very aware populace has exerted pressure on its legislators to enact enforcement laws dealing with pollution. Among the different types of pollution, sulfur dioxide in the air is a large and readily identifiable constituent. Air pollution, according to the EPA, costs the U, S. billions annually with SO2 a major portion of this cost. Fossil fuel and oil fired power plants release better than 50% of the SO2 in the country. Thus great attention is being focused on the methods power plants are utilizing to control emissions. With a time schedule of compliance by early 1975, decisions are being made and systems chosen that will have to perform - and perform - and perform. Therefore, a large majority of the power plants are presently considering lime in the planning and operational phases of their stack gas desulfurization programs. The reasons for this are: Lime scrubbing has more development and pilot work completed than most other methods; the removal potentials are relatively high; the stoichiometric ratios are not excessive and, the process has relatively low capital and operating costs. Many pilot plant studies have been completed recently using lime and the first operational full scale lime scrubbing unit is now in the start-up phase at this time at Duquesne Light Company's Phillips Station here in Pittsburgh. Also, because of completed development work, the problem of solid waste disposal will also be tackled at this power station at the same time. There are various methods for the use of lime in scrubbing for S02, but for our purposes I would like to describe the cyclic wet lime process. This method called "Scrubber Addition of Lime" involves contacting the flue gas with a slurry of milk of lime.

Jan 1, 1973

By J. G. Davis

Continental Oil Company has spent over four years of research on the fundamentals of potash solution mining. This work included laboratory investigations of salt solution, brine flow, selective extraction of KC1 from sylvinite, and control of cavity geometry. Laboratory results were expanded by means of a series of field tests, and subjects such as well completion and hydraulic fracturing were added to the investigation. Both single-well and multi-well mining systems were studied in the field work. The current paper discusses one field test in which potash was solution mined from a thin sylvinite ore zone in the Carlsbad Potash Basin. A two-well mining system was used for this test. The potential economic value of solution mining has been recognized for many years, and applicable United States patents date back into the past century. Principal advantages of the process over conventional mining include (1) the use of drilled holes and solution techniques in- stead of excavated shafts and caverns and (2) the ability to mine both land and marine deposits through any type of overburden geology and below conventional mining depths.

Jan 1, 1969

By A. E. Hunt

Over the past twenty-live years since large scale truck haulage in open-pit mining began, the periodic introduction of Larger capacity vehicles has provided increased productivity and reduced costs. WISEDA Ltd. has introduced a 220 ton capacity, two-axle rear dump, diesel-electric truck for the world-wide large open-pit mining industry. Design features and components selected in the development of this vehicle will be presented along with operating experience and a brief history of rear dump truck evolution.

Jan 1, 1983

By P. C. Thakur

Horizontal drilling in coal mines is a relatively new technology. The earliest recorded drilling in the United States was done in 1952 at the Humphrey Mine of Consolidation Coal Company for degasification of coal seams. Spindler and Poundstone experimented with vertical and horizontal holes for eight years. They concluded in 1960 that horizontal drilling in advance of underground mining appeared to offer the most promising prospect (for degasification) but effective and extensive application would be dependent upon the ability to drill long holes, possibly 300-to 600 m, with reasonably precise directional control and within practical cost limits.(1) Mining Research Division of Continental Oil Company, the parent company of Consolidation Coal Company, began a research program in the early 1970's to achieve the above objective. The technology needed to drill nearly 300 m in advance of working faces was developed by 1975 and experiments on advance degasification with such deep holes began in 1976. Preliminary Its of this research have already been published.(2) To date nearly 4500 m of horizontal holes have been drilled for advance degasification and earlier results were reconfirmed. In summary, these are: 1) The greatest impact of these boreholes was felt in the face area where methane concentrations were reduced to nearly 0.3 percent in course of two to three months from original values of nearly 0.95 percent.

Jan 1, 1979

By RALPH BALTES, AMIR EHSAN KIANFAR, FABIAN UTH, ELISABETH CLAUSEN

  Underground positioning and communication are essential technologies for the future of underground mining operations. In contrast to other positioning and communication technologies such as wireless local area network (WLAN) or radio frequency identification (RFID), ultra-wideband (UWB) radio technology provides significant benefits like accurate and robust positioning of mobile machine equipment, which is indispensable for future autonomous systems in underground mining processes, such as production, transportation and auxiliary operations. Among these technologies, UWB offers many advantages, including higher accuracy, robustness, resistance against noise and multipath effects, and low power consumption [1,2]. Underground automation and localization systems benefit from these advantages and use the technology to improve efficiency and safety. There are many studies being carried out on this technology to increase the results’ accuracy, energy sufficiency and more. Two robust UWB modules that were developed for underground positioning and collision avoidance with regard to human safety in underground mining operations are introduced. The measurement results of tests carried out in an underground mine are discussed as well to confirm the functionality of the system.

By R. L. Miller

The potential for recovery of enriched uranium from spent nuclear fuel which has been consolidated into a nuclear waste form was explored in the studies reported here. The waste form of interest is iron-enriched basalt (IEB)--a silicate-based, fused-cast ceramic. IEB samples were prepared containing fuel assembly materials that simulate the core debris of Three Mile Island Unit II;1,2 the nominal composition of the consolidated waste form is given in Table 1. Ore Types The IEB samples, or man-made uranium ores (MMUO), are in two different mineralogical forms. Each MU0 was made by melting the constituent materials and holding at about 1500°C for 1 h. The MMUOs were then heat treated to control crystallization and crystal growth and then cooled to room temperature.

Jan 1, 1983